Living the high life is risky business for midwive's in Iberia

Walker et al. have published their long-awaited survey of the prevalence of Bd across the Iberian peninsula in Ecology Letters. The study focuses on common midwives, Alytes muletensis, and combines multilocus genotyping with bayesian analyses to show that Bd is not at equilibrium within Iberia, but is still spreading. While lowland populations of Alytes appear to co-exist with the chytrid, high-altitude populations exhibit chytridiomycosis and seasonal die-offs, demonstrating a very strong interaction between altitude/temperature and disease. Within a key region, the Pyrenean mountain range, Bd is absent across the majority of the range except for a tight cluster of genotypically-identical Bd strains in the western Pyrenean National Park. How Bd arrived in this region is not known: there are no known introduced non-native amphibian species in this area however the montane lakes are regularly 'seeded' with salmonid fish for the angling industry. Efforts now need to focus on the process of introduction and spread, as it is a key concern to prevent the wider spread of Bd throughout this ecologically sensitive region.